Note: Descriptions are shown in the official language in which they were submitted.
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Tk-A,1" FOR BURROWING APi1MALS
This invcntion relates to traps and in particular to traps set at the opening
of a burrow
made by a burrowing animal.
$ACKGR(HJND
Burrowing animals such as gophers and ground hogs cause considerable daniage
to
fields, gardens, and like agricultural and horticultural locations. These
animals typically
dig tunnels or but-rows where they live, disrupting the soil surface for a
considerable area
around the mouth or entrance of the burrows. The aninrals leave the burrow to
find food,
and that food commonly comprises desirable horticultural and agricultural
plants growing
close by, destroying the plants.
Thus considerable effort has been directed toward designing traps suitable to
trap and kill
burrowing animals. These traps are generally of two types - thosc traps where
the animal
is grasped by the trap, and those where it is stabbed or impaled by the trap.
Stabbing
trap-i typically include sharpened forks or spikes that are forced downward by
a spring
into an animal that. trips a trigger.
Stabbing traps are disclosed for example in United States Patent Numbers
598,262 to
Renken, 687,226 to Gorr, and 861,174 to Heil. These traps include stakes at
bottoms
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thereof and are positioned in a Eocation where a bttnowinC animal is likely to
pass, for
exatnple ovcr or near the mouth of a burrow, by pushing the stakes into the
ground.
Another stabbing trap, clisctosed in United States Patent Number 954,996 again
to
Renken is located by niaking an excavation and seating the trap at or near the
entrance of
the burrow.
Stabbing traps are messy, as blood and gore is tiecessarily spread about in
the area when
an animal is stabbed. The resulting mcss is distasteful.
Grasping traps in contrast can simply hold the animal, or more commonly kill
the animal
by strangulation, as it is often the neck area where pressure is applied by
these traps.
Blood and gore generally does not result from using grasping traps. Examples
of
graspiug traps for use with burrowing animals are disclosed in United States
Patent
Numbers 2,603,029 to Anderson, 2, 475,467 to Alvau, and 2.148,813 to Hosnier.
For use
with burrowing animals, it is described that an excavation is made to place
thcm in the
underground burrow in the path of the burrowing animals. Thus it is required
to locate
the burrow underground, which can be problematic.
United Statcs Patent Number 2,059,164 to Woods discloses a trap similar to
that of
Andenon, hut no directions are given for use with burrowitig animals, and it
is described
as being used to hang over an animal hole in a wall.
. , ,
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SUMMARY OF THC IIN7N'ENTION
It is an object of the present invention to provide a trap for buirowiug
aninials that
overcomes problems in the prior art.
In a first. embodiment the present invention provides a trap apparatus
comprising an
elongated base plate defining a trap aperture in a lower portion thereof, and
a pointed
bottom end below the trap aperture. Slide grooves are defined along each side
of the base
plate adjacent to a first surface of the base plate. A trigger arm has a lower
end extending
over the trap aperture, and is pivotally attached at an upper end thereof to
thc basc plate at
a pivot location in a middle portion of the base plate above the trap aperture
such that the
trigger arm can move away from and toward the first surface of the basc plate.
A slide
plate is engaged in the slide grooves such that the slide plate canslide up
and down in the
grooves between the trigger arm and the first surface of the base plate from a
raised
cocked position where a lower edge of the slide plate is substantially above
the trap
aperture, to a lower tripped position wherein the lower edge of the slide
plate extends
across the trap aperture. A bias element is opcrative, when the slide plate is
in the cocked
position, to exert a downward bias force on the slide plate toward the tripped
position.
An arm t.rip element is mounted on a rniddle portion of the trigger atzn and
configured to
engage a cotre.sponding slide trip elentent mounted on a middle portion of the
slide plate
to maintain the slide plate in the cocked position. Nlovement of the lower end
of the
trigger arm away from the base plate releases the arm trip element From
engagement with
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the slide trip clcmctit and allows the slide plate to move to tltc tripped
position in
response to the bias force.
In a second embodintent the present invention provides method of trapping a
burrowing
anima{ where the burrowing animal makes a burrow with an entrance hole
comprising a
crater with sloped walls, and a burrow mouth in a sloped wall of the crater.
The method
comprises providing a trap apparatus comprising un elongated base plate
defitting a trap
aperture in a lower portion thereof, and a pointed bottom end below the trap
aperture:
slide grooves defined along each side of the base plate adjacent to a first
surface of the
base plate; a trigger arm having a lower end extending over the trap aperture,
and
pivotally attached at an upper end thereof to the batie plate at a pivot
location in a middle
portion of the base plate above the trap aperture such that the trigger arnt
can move away
from and toward the first surface of the base plate; a slide plate engaged in
the slide
grooves such that the slide plate can slide up and down in the grooves between
the trigger
ann and the first surface of the base plate from a raised cocked position
where a lower
edge of the slide plate is substantially above the trap aperture, to a{ower
tripped position
wherein the lower edge of the slide plate extends across the trap aperture; a
bias elerrtent
operative, when the slide plate is in the cocked position, to exert a downward
bias force
on the slide plate toward the tripped position; an arm trip element mounted on
a middle
portion of the trigger arm aiid configured to engage a corresponding slide
trip elernent
mounted on a middle portion of the slide plate to maintain tlte slide plate in
the cocked
position; wherein movement of the lower end of the trigger arm away froin the
base plate
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releases the arm trip elernent from engagcment with the slide trip clcment and
allows the
slide plate to move to the tripped posidon in response to ttle bias force. The
pointed
bottom end of the base plate is pushed into the ground at the bottom of the
crater such
that the base plate is supported in the ground with a second surface of the
base plate
facing the burmw mouth and the trap apertttre aligned with the burrow mouth
and the
lower end of the trigger artn extcnding over the trap aperture oppocite the
burrow ntouth
such that a burrowing animal exiting the burrow will contact the lower end of
the trigger
arm and push the lower end of the trigger arm away from the base plate. The
slide plate
is moved to the raised cocked position and the arm trip element and the slide
trip element
are engaged to maintain the slide plate in the cocked position.
The present inventor has recognized that the entrance to a burmw, for
burrowing animals
like gophers in any event, is most commonly quite wide compared to the burrow
itself,
rather than a substantially horizontally oriented hole in the ground surface,
for example as
illustrated in the prior 898,262 patent of Renken. As a result the entrance is
typically a
crater like depression with a burrow leading off at a downward angle froni the
bottom of
the sloping wall of the crater and the mouth of the burrow formed in the
sloping wall.
The crater wall thus allows the present trap to be conveniently stuck into the
;round with
the trap opening coincidental with the burrow mouth at the bottom of the
crater wall.
The trap apparatus is siunple and economical to manufacture and assemblc, and
conipact
to Cacilitate shipping.
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DES{."RIPi'ION f)I' TFIE DRAWL'VGS
Wliile the invention is claimed in the concluding portions hereof, preferred
embodiments
are provided in the accompanyin.g detailed description which may be best
understood in
conjunction with the accompanying diagrams where like parts in each of the
several
diagrams are labeled with like numbers, and where:
Fig. I is a perspective view of disassembled parts of an einbodiment of a trap
apparatus
to of the present invention;
Fig. 2is a perspective view of the embodiment of Fig. 1 with parts assembled
and bias
element installed;
Fig. 3 is a schematic sectional side view of the trap apparatus of Fig. I
installed in the
entrance of a burrow of an animal to be trapped.
DETAILED DESCRIPTIC}N OF THE ILLUSTRATED E13MODDIENTS
Figs.1 and 2 illustrate an enibodiment of a trap apparatus I of the present
invention. The
apparatus 1 comprises an elongated base plate 3 defining a trap aperture 5 in
a lower
portion thereof, and a pointed bottom end 7 below the trap apertttre 5. The
trap aperture 5
~, ,.
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is configured to allow a burrowing auimal that i:s to he trapped to pass
therethrough.
Slide grooves 9 are defined along each side of the base plate 3 adjaccnt to a
first surface
I I of the base plate 3.
The illu.strated base plate 3 includes right and left side walls 4 extending
upward along
corresponding right and left sides of the base plate 3 abovc the grooves 9.
The walls 4
somewhat reduce the occurrencc of soil fouling the grooves 9 during use by
preventing
soii front falling onto the tirst surface 11.
A trigger arm 13 has a lower enci 15 extending over the tra.p szperture 5, and
pivotally
attached at an tipper end 17 thereof to ihe base plate 3 at a pivot location
in a niiddle
portion of the base plate 3 above the trap aperture 5 such that thc triggcr
arm 13 can move
away from and toward the first sutface 11 of the base plate 3. The illustrated
trigger arm
13 is attached to a eross member 14 that extends from one side wall to the
other and
througlt holes 16 in the walls 4 such that the cross member 14 can rotate in
the holes 16 to
allow the trigger arm 13 to pivot to move away from and toward the first
surface 11 of
the base plate 13.
A slide plate 19 is engaged in the slide grooves 9 such that the slide plate
19 can slide up
and down in the grooves 9 between the trigger arm 13 and the base plate 3
frotn a raised
cocked position, illustrated in Fig. 2 where a lower edge 21 of the slide
plate 19 is above
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the trap aperture 5, to a lower tripped position wherein the lower edge 21 of
the slide
plate 19 extends across the trap aperture 5.
A bias elentent, illustrated as spring 23, is opcrative, when the slide plate
19 is in the
cocked position of Fig. 2, to exett a downward bias force BF on the slide
plate 19 toward
the tripped position. 'rhe spring 23 is connected between the cross member 14
and a
flange 25 extending up from the top end of the slide plate 19.
An arm trip element, illustrated as an arm lug 27 extends from the middle
portion of the
arm 13 toward the base plate 3, and is configured to engage a corresponding
slide trip
clcment, illustrated as a slide lug 29 extending from the middle portion of
the slide plate
19 toward the arm 13, to maintain the slide plate 19 in the cocked position.
In the
illustrated embodiment, the atm lug 27 is conveniently provided by bending the
trigger
arm 13 iirto a kink at a niidpoint thereof, and the slide lug 29 is
conveniently provided by
punching a flap out of the slide plate 19 and bending up the punched out flap.
Depending
on the ntaterials used, the lugs 27, 29 can be provided in a variety of ways.
When engaged as in Fig. 2, the slide lug 29 bears against the arm lug 27 in
response to
the bias force BF exerted on the slide plate 19. Movement of the lower end 15
of the
trigger :unt 13 away froni the base plate 3 moves the arm lug 27 up to release
the slide
lug 29 and allows the slide plate 19 to move to the tripped position in
response to the bias
force BF.
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Fig. 3 illustrates a method of trapping a burrowing animal where the burrowing
animal
makcs a burrow 30 with aii entrance hole comprising a crater 31 with sloped
walls 33,
and a burrow mouth 35 in the sloped wall 33. The inethod comprises providing a
trap
apparatus i of Figs. 1 and 2, and pushing the pointed bottom end 7 of the base
plate 3 into
the ground at the bottom of the crater such that the base plate 3 is supported
in the ground
with a second surface 37 of the base plate 3. opposite the trigger ai-m 13,
facing the
burrow mouth 35 and the trap aperture 5 aligned with ttte burrow mouth 35 and
the lower
end 15 of the trigger arm 13 extending over the trap aperture 5 opposite the
burrow
mouth 35,
The slide plate 19 is raised to the cocked position atid the arm lug and the
slide lug are
engaged to maintain the slide plate 19 in the cocked position. A burrowing
animal
exiting the burrow 30 will contact the lower end 15 of the triggcr arm 13 and
push it
away from the base plate 3, tripping the slide plate 19 and catching the
animal. Typically
the lowcr edge of the slide plate 19 will coutact the animal's neck. forcing
it against the
opposite edge of the trap aperttire 5, and choking the animal.
The animal is removed from the trap by simply grasping the top end of the
apparatus 1
and pulling back the slide plate 19 to release the animal, conveniently into a
pail or like
container to be taken away for disposal. The slide plate 19 can then be cocked
again and
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the apparatus I pushed into the grottnd adjacent the same burrow mouth 30, or
another
one.
The lower end 15 of the trigger arm 13 is Y-shaped to substantially prevent a
burrowing
animal froin enterine the bunow mouth 30. A burrowing aitimal, or any other
animal,
atternpting to enter the mottth 30 will be blocked and even if tripped by an
animal on the
uutside the trap is not likely to cause significant liarrn to the animal. At
the satne tiine,
the butrowing animal leaving the burrow will see a space between the arms of
the Y and
not be detetred from attetnpting to leave.
The foregoing is considered as illustrative only of the principles of the
uivention.
Further, siitce numerous changes and modifications will readily occur to those
skilled in
the art, it is not desired to limit the invention to the exact constntction
and operation
shown and described, aitd accordingly, all such suitable changes or
rnodification.s in
stntcture or operation which may be resorted to are intended to fall within
the scope of
the claimed invention.
